Hi, I am trying to set up an automatic connection between CentOS 4 system (server) and a CentOS 5 DomU VM (client) via ssh to enable my to back up development files on the server to the client with a cron process. I generate they key pair without a pass phrase on the client and copy the public key to the same user's .ssh directory on the server as authorized_keys2. When I try to ssh to the Server from the Client, I am still asked for the user's password on the client. If I do the same with CentOS 5 for both Client and Server, I can login without providing a password. The versions of ssh on the two systems are: Client (CentOS 5): OpenSSH_4.3p2, OpenSSL 0.9.8b 04 May 2006 Server (CentOS 4): OpenSSH_3.9p1, OpenSSL 0.9.7a Feb 19 2003 Does anyone on the list know whether these versions are compatible or how to get them to work together without requiring a password. It is not an option to change to CentOS5 on the server side as that system is serving as a development system for a client running RedHat ES 4 and has to have the identical configuration and be binary compatible. TIA ChrisG